We currently don't use the initial-setup application in the main KDE Spin and Kinoite installation ISOs as everything gets configured at installation time via Anaconda. We thus want to remove this package from the installation ISOs while keeping it where we currently need it (pre-installed disk images, etc.). Note that an "initial setup" app is still needed to enable OEM-style installations (https://askubuntu.com/questions/1386806/what-is-oem-installation-regarding-l...) of the KDE Spin/Kinoite (like Fedora Workstation/Silverblue) so we're planning on introducing a more KDE native application as a replacement once it is ready, but that may not not happen as part of this change.
How about Calamares in a dont-chroot: true configuration?
Kevin Kofler